Antigen presentation induced variation in ovalbumin sensitization between chicken and duck species.

The difference in the allergenicity of chicken ovalbumin (C-OVA) and duck ovalbumin (D-OVA) can be related to their differences in antigen presentation. This study explored the differences in uptake between C-OVA and D-OVA through fluorescence dye-labeling, DC antigen presentation, and the immune response of T cells by using C-OVA and D-OVA allergic animal and cell models. The ileum DCs of mice in the C-C group took up more C-OVA than that of D-D and C-D groups through in vivo imaging. Furthermore, C-OVA induced the maturation of DCs in mice in the C-C group as shown in the up-regulation of the expressions of MHC II, CD86 and CD80 on the surface of DCs, and enhanced the ability of antigen presentation. In addition, C-OVA induced the maturation of DCs, promoted the differentiation of T cells into Th2 cells, increased the secretion of the cytokine IL-4 and specific antibody s-IgE, and thus generated an immune response. However, sensitized and cross sensitized D-OVA (D-D and C-D groups) couldn't induce the maturation of DCs, and induced less differentiation of T cells and lower secretion of cytokines compared to C-OVA. In conclusion, the differences in antigen presentation was one of the important factors resulting in the differences in the sensitization between C-OVA and D-OVA.

Cow's milk αS1-casein is more sensitizing than goat's milk αS1-casein in a mouse model.

The aim of this study was to compare the sensitization of αS1-CN in cow and goat's milk in a mouse model. Fifty mice were divided into control group, adjuvant control group, cow's milk αS1-CN sensitized group, goat's milk αS1-CN sensitized group and cross sensitized group. Cow's and goat's milk αS1-CN were used to establish a mouse sensitization model. The results showed that cow's milk αS1-CN had higher allergenicity than goat's milk αS1-CN, as can be seen in significantly increased s-IgE and Th2 cell-related inflammatory factors, the proportion of Th2, and the expression of Th2 cell-related transcription factors. Furthermore, the sensitization of cow's milk αS1-CN damaged the intestinal barrier of mice, caused the leakage of LPS, activated the TLR4-NFκB pathway, and thus resulted in the increase of IFN-γ. In addition, mice allergic to cow's milk αS1-CN were less sensitized to goat's milk αS1-CN.